With a machine for the vertical and/or horizontal cleaning of clinkers, cobblestones, natural stone, tiles, brick, external plaster, etc. inter alia, scrubbing, sweeping and/or polishing machines are meant. These can be driven by electrical, hydraulic, pneumatic or similar means.
Surfaces which are provided with grooves, joints, unevennesses and/or pores are, inter alia, clinkers, cobblestones, natural stone, tiles, brick, external plaster, road pavement (VPA=very porous asphalt and VPAC=very porous asphalt concrete), and/or metal and/or wood.
Concerning the cleaning of several surfaces which are separated by grooves, joints, unevennesses and/or pores, it is known to use high-pressure cleaning or cleaning with chemical products. Therewith, said surfaces are hosed down by means of a water jet, sandblast and/or water-sand jet under high pressure (from 120 bar). In the case of chemical cleaning, chemical products are applied to said surfaces. The chemical products act on the dirt which is present. After a soak-in period, any dirt which is present and the chemical products are sprayed away.
However, there are several drawbacks associated with high-pressure and chemical cleaning, i.e.                the grooves, joints, unevennesses and/or pores between the surfaces are not deep-cleaned;        the several surfaces which are separated from one another by means of grooves, joints, unevennesses and/or pores are often damaged by the high-pressure force of the water and/or the sand;        large amounts of water are required;        in some cases, a large amount of cleaning products have to be used;        the water and sand splashes, as a result of which surfaces surrounding the surface to be cleaned, such as, inter alia, walls and/or windows, are soiled;        high-pressure cleaning is labour-intensive. Thus, it takes on average 8 hours to clean a surface of approximately 100 m2 consisting of clinkers, cobblestones, natural stone and/or tiles. This includes introducing new sand in the grooves, joints, unevennesses and/or pores when required, and includes cleaning the surrounding soiled surfaces;        after cleaning with high pressure, the clinkers, cobblestones, etc. become loose, as a result of which it takes a long time before one can drive over the cleaned surface again;        stubborn dirt, such as, inter alia, lichens, are difficult to remove by high-pressure cleaning;        the noise pollution caused by the high-pressure cleaner;        the chemical products are detrimental to the surface consisting of clinkers, natural stone, tiles, brick, external plaster, metal and/or wood;        the chemical products are harmful to the environment: humans, animals and plants. A European decree (becoming effective in 2012) prohibits the further use of herbicides by municipalities, cities and government bodies to combat weeds on car parks, cycling paths and footpaths and the like.        
This problem has already been solved by BE 1 017 134, which discloses a brush for a scrubbing, sweeping and/or polishing machine for machine-cleaning of several surfaces which are separated from one another by means of grooves and/or joints, wherein this scrubbing, sweeping and polishing machine is provided with one or several brushes which comprise at least one set of polishing hairs for cleaning and/or polishing the surfaces, and at least one set of joint hairs for cleaning the grooves and/or the joints between the surfaces, wherein the polishing hairs have a length which is shorter than the length of the joint hairs, and which discloses a machine which is provided with one or several of such brushes.
A drawback of this brush is that the joint hairs wear and become as short as the polishing hairs of the brush, as a result of which it is no longer possible to clean grooves, joints, unevennesses and/or pores using this brush. A drawback of the wear of the joint hairs is the fact that the brush no longer moves in the vertical direction, as a result of which surfaces are cleaned less efficiently. A further drawback of such a brush is the fact that different brushes are required for different surfaces and/or different kinds of soiling in order to achieve efficient cleaning. For the efficient cleaning of cobblestones, for example, the brush needs to contain more steel hairs than are required for the efficient cleaning of natural stone. Thus, these two different surfaces require two different brushes.